<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd">
<!-- saved from url=(0013)about:internet -->
<?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" xmlns:xlink="http://www.w3.org/1999/xlink" pref:renderer="mathplayer-dl">
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
    <style xmlns="" type="text/css">
    /* This style sets a margin around the entire page */
        html, body {
            margin: 10px;
        }

        p {
            font: normal 16px verdana, sans-serif;
            margin: 0;
            padding-bottom:12px;
        }

        h1 {
            font: bold 25px verdana, sans-serif;
            margin-top: 0;
            margin-bottom: 3px;
            padding-top: 0;
            padding-bottom: 0;
        }

        h2 {
            font: bold 19px verdana, sans-serif;
            margin-top: 28px;
            margin-bottom: 3px;
            padding-top: 0;
            padding-bottom: 0;
        }

        h3 {
            font: bold 19px verdana, sans-serif !important;
            margin-top: 28px;
            margin-bottom: 3px;
            padding-top: 0;
            padding-bottom: 0;
        }

        li {
            font: normal 16px verdana, sans-serif;
            margin-top: 0;
            margin-bottom: 18px;
            padding-top: 0;
            padding-bottom: 0;
        }

        .pdparam {
            font: italic 16px verdana, sans-serif;
        }

                .term {
                        font: italic 16px verdana, sans-serif;
                        font-weight: normal;
                }

                .type {
                        font: normal 16px verdana, sans-serif !important;
                }

                .parameter {
                        font-style: italic;
                        }

        a:link, a:visited {
            color: blue;
            text-decoration: none;
            font: normal 16px;
        }

        a:hover {
            background-color: #FFFF99;
            font: normal 16px;
        }

        div.funcsynopsis {
            text-align: left;
            background-color: #e6e6e6;
            font: normal 16px verdana, sans-serif;
                        padding-top: 10px;
                        padding-bottom: 10px;
        }

        div.funcsynopsis table {
            border-collapse: separate;
            font: normal 16px verdana, sans-serif;
        }

        div.funcsynopsis td {
            background-color: #e6e6e6;
            border: 0 solid #000;
            padding: 1px;
            font: normal 16px verdana, sans-serif;
        }

        div.refsect1 {
            font-family: verdana, sans-serif;
            font-size: 16px;
        }

        code.constant {
            font: normal 16px courier new, monospace !important;
        }

                span.errorname {
            font: normal 16px verdana, sans-serif !important;
        }

        code.function {
            font: bold 16px verdana, sans-serif !important;
        }

        b.fsfunc {
            font: bold 16px verdana, sans-serif !important;
        }

        code.varname {
            font: italic 16px verdana, sans-serif;
        }

        code.replaceable {
            font: italic 16px courier new, monospace;
        }

        code.funcdef {
            font: normal 16px verdana, sans-serif !important;
        }

        .citerefentry {
            font: normal 16px verdana, sans-serif !important;
        }

        .parameter {
            font-style: italic;
        }

        code.fsfunc {
            font: normal 16px verdana, sans-serif !important;
        }

        /* PARAMETER: This style controls spacing between the terms in Parameter section */
        dt {
            margin-top: 15px;
        }

        /* TABLES: These styles apply to all tables OTHER than the Synopsis and Example tables */
        div.refsect1 table {
            width: 100%;
                        margin-top: 10px;
            background-color: #FFF;
                        border-collapse: collapse;
                        border-color: #000;
            border-width: 1px;
                        font: normal 16px verdana, sans-serif;
        }

        div.refsect1 th {
                        border-collapse: collapse;
                        border-color: #000;
            border-width: 1px;
            font: bold 16px verdana, sans-serif;
        }

        div.refsect1 td {
            background-color: #FFF;
            padding: 5px;
            vertical-align: text-top;
                        border-collapse: collapse;
                        border-color: #000;
            border-width: 1px;
            font: normal 16px verdana, sans-serif;
        }

                  div.refsect1 p{
            font: normal 16px verdana, sans-serif;
            margin-top: 8px;
            margin-bottom: 8px;
            padding-top: 0;
            padding-bottom: 0;
        }


        /* EXAMPLE: These styles apply only to the Example section */
        div.refsect2 {
            font: normal 16px courier new, monospace !important;
        }

        div.refsect2 table {
            margin-top: 0;
            background-color: #e6e6e6;
            width: 100%;
            border: 0 solid #000;
            padding: 2px;
            font: normal 16px courier new, monospace !important;
        }

        div.refsect2 td {
            background-color: #e6e6e6;
            font: normal 16px courier new, monospace !important;
                        white-space:pre;
        }

        /* COPYRIGHT: This style formats the text of the copyright statement at the bottom of the page */
        div.refsect3 {
            font: normal 11px verdana, sans-serif;
            margin-top: 50px;
            margin-bottom: 20px;
            padding-top: 0;
            padding-bottom: 0;
        }

</style>
    <title>clGetGLContextInfoKHR</title>
    <meta name="generator" content="DocBook XSL Stylesheets V1.78.1" />
    <meta name="keywords" content="clGetGLContextInfoKHR" />
  </head>
  <body>
    <div class="refentry">
      <a id="id-1"></a>
      <div class="titlepage"></div>
      <div xmlns="" class="refnamediv">
        <a xmlns="http://www.w3.org/1999/xhtml" id="clGetGLContextInfoKHR"></a>
        <h1>
            clGetGLContextInfoKHR
        </h1>
        <p>
             Get OpenGL context information.
        </p>
      </div>
      <div class="refsynopsisdiv">
        <h2></h2>
        <div class="funcsynopsis">
          <table xmlns="" border="0" summary="Function synopsis" cellspacing="0" cellpadding="0">
            <tr valign="bottom">
              <td>
                <code xmlns="http://www.w3.org/1999/xhtml" class="funcdef">
                    <a class="link" href="scalarDataTypes.html" target="pagedisplay">cl_int</a>
                    <strong class="fsfunc">clGetGLContextInfoKHR</strong>
                (</code>
                <td>const
                    <a xmlns="http://www.w3.org/1999/xhtml" class="link" href="enums.html#cl_context_properties" target="pagedisplay">cl_context_properties</a>
                     <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">*properties</var>
                , </td>
              </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td>
                    <a xmlns="http://www.w3.org/1999/xhtml" class="link" href="enums.html#cl_gl_context_info" target="pagedisplay">cl_gl_context_info</a>
                     <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">param_name</var>
                , </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td>
                    <a xmlns="http://www.w3.org/1999/xhtml" class="link" href="scalarDataTypes.html" target="pagedisplay">size_t</a>
                     <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">param_value_size</var>
                , </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td>
                    <a xmlns="http://www.w3.org/1999/xhtml" class="link" href="scalarDataTypes.html" target="pagedisplay">void</a>
                     <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">*param_value</var>
                , </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td>
                    <a xmlns="http://www.w3.org/1999/xhtml" class="link" href="scalarDataTypes.html" target="pagedisplay">size_t</a>
                     <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">*param_value_size_ret</var>
                <code>)</code></td>
            </tr>
          </table>
        </div>
      </div>
      <div class="refsect1">
        <a id="parameters"></a>
        <h2>Parameters</h2>
        <div class="variablelist">
          <dl class="variablelist">
            <dt>
              <span class="term"> <code class="varname">properties</code> </span>
            </dt>
            <dd>
              <p>
                      Points to an attribute list whose format and valid contents
                      are identical to the <code class="varname">properties</code> argument of
                      <a class="citerefentry" href="clCreateContext.html"><span class="citerefentry"><span class="refentrytitle">clCreateContext</span></span></a>.
                      <code class="varname">properties</code> must identify a single valid GL context or
                      GL share group object.
                    </p>
            </dd>
            <dt>
              <span class="term"> <code class="varname">param_name</code> </span>
            </dt>
            <dd>
              <p>
                      A constant that specifies the GL context information to query, and must
                      be one of the values shown in the table below.
                    </p>
            </dd>
            <dt>
              <span class="term"> <code class="varname">param_value_size</code> </span>
            </dt>
            <dd>
              <p>
                      Specifies the size in bytes of memory pointed to by
                      <code class="varname">param_value</code>.  This size must be greater than or equal
                      to the size of the return type described in the table below.
                    </p>
            </dd>
            <dt>
              <span class="term"> <code class="varname">param_value</code> </span>
            </dt>
            <dd>
              <p>
                      A pointer to memory where the result of the query is returned as described
                      in the table below. If <code class="varname">param_value</code> is NULL, it is ignored.
                    </p>
            </dd>
            <dt>
              <span class="term"> <code class="varname">param_value_size_ret</code> </span>
            </dt>
            <dd>
              <p>
                      Returns the actual size in bytes of data being queried by
                      <code class="varname">param_value</code>.  If <code class="varname">param_value_size_ret</code>
                      is NULL, it is ignored.
                    </p>
            </dd>
          </dl>
        </div>
        <div class="informaltable">
          <table border="1">
            <colgroup>
              <col align="left" class="col1" />
              <col align="left" class="col2" />
              <col align="left" class="col3" />
            </colgroup>
            <thead>
              <tr>
                <th align="left">param_name</th>
                <th align="left">Return Type</th>
                <th align="left">Information returned in param_value</th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td align="left">
                  <code class="constant">CL_CURRENT_DEVICE_FOR_GL_CONTEXT_KHR</code>
                </td>
                <td align="left">cl_device_id</td>
                <td align="left">Return the CL device currently associated with the specified OpenGL context.</td>
              </tr>
              <tr>
                <td align="left">
                  <code class="constant">CL_DEVICES_FOR_GL_CONTEXT_KHR</code>
                </td>
                <td align="left">cl_device_id[]</td>
                <td align="left">List of all CL devices which may be associated with the specified OpenGL context.</td>
              </tr>
            </tbody>
          </table>
        </div>
      </div>
      <div class="refsect1">
        <a id="description"></a>
        <h2>Description</h2>
        <p>
          The OpenGL object used to create the OpenCL memory object and information about
          the object type i.e. whether it is a texture, renderbuffer, or buffer object can be
          queried using this function.
        </p>
      </div>
      <div class="refsect1">
        <a id="notes"></a>
        <h2>Notes</h2>
        <p>
           The OpenCL specification in section 9.7 defines how to
          share data with texture and buffer objects in a parallel OpenGL implementation,
          but does not define how the association between an OpenCL context and an OpenGL
          context or share group is established. This extension defines optional attributes
          to OpenCL context creation routines which associate a GL context or share group
          object with a newly created OpenCL context. If this extension is supported
          by an implementation, the string "cl_khr_gl_sharing" will be present in the
          <code class="constant">CL_PLATFORM_EXTENSIONS</code> or <code class="constant">CL_DEVICE_EXTENSIONS</code>
          string described in the table of allowed values for <code class="varname">param_name</code>
          for <a class="citerefentry" href="clGetDeviceInfo.html"><span class="citerefentry"><span class="refentrytitle">clGetDeviceInfo</span></span></a>.
        </p>
        <p>
           An OpenGL implementation supporting buffer objects and
          sharing of texture and buffer object images with OpenCL is required by this extension.
        </p>
        <p>
           OpenCL device(s) corresponding to an OpenGL context may be
          queried. Such a device may not always exist (for example, if an OpenGL context is
          specified on a GPU not supporting OpenCL command queues, but which does support shared
          CL/GL objects), and if it does exist, may change over time. When such a device does
          exist, acquiring and releasing shared CL/GL objects may be faster on a command queue
          corresponding to this device than on command queues corresponding to other devices
          available to an OpenCL context.
        </p>
      </div>
      <div class="refsect1">
        <a id="errors"></a>
        <h2>Errors</h2>
        <p>
          Returns <span class="errorname">CL_SUCCESS</span> if the function is executed successfully.
          If no device(s) exist corresponding to <code class="varname">param_name</code>, the call will not
          fail, but the value of <code class="varname">param_value_size_ret</code> will be zero. Otherwise
          returns one of the following:
        </p>
        <div class="itemizedlist">
          <ul class="itemizedlist" style="list-style-type: disc; ">
            <li class="listitem" style="list-style-type: disc">
              <p>
                    <span class="errorname">CL_INVALID_GL_SHAREGROUP_REFERENCE_KHR</span> when an
                    invalid OpenGL context or share group object handle is specified in
                    <code class="varname">properties</code>.
                </p>
            </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_GL_SHAREGROUP_REFERENCE_KHR</span> if a context was
                    specified by any of the following means:

                <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem" style="list-style-type: disc"> A context was specified for an
                      EGL-based OpenGL ES or OpenGL implementation by setting
                      the attributes <code class="constant">CL_GL_CONTEXT_KHR</code> and
                      <code class="constant">CL_EGL_DISPLAY_KHR</code></li><li class="listitem" style="list-style-type: disc"> A context was specified
                      for a GLX-based OpenGL implementation by setting the
                      attributes <code class="constant">CL_GL_CONTEXT_KHR</code> and
                      <code class="constant">CL_GLX_DISPLAY_KHR</code></li><li class="listitem" style="list-style-type: disc"> A context was specified
                      for a WGL-based OpenGL implementation by setting the
                      attributes <code class="constant">CL_GL_CONTEXT_KHR</code> and
                      <code class="constant">CL_WGL_HDC_KHR</code></li></ul></div><p>
                    and any of the following conditions hold:
                </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem" style="list-style-type: disc"> The specified display and context attributes do
                      not identify a valid OpenGL or OpenGL ES context.
                    </li><li class="listitem" style="list-style-type: disc">
                        The specified context does not support buffer and renderbuffer objects.
                    </li><li class="listitem" style="list-style-type: disc"> The specified context is not compatible with
                      the OpenCL context being created (for example, it exists in a physically
                      distinct address space, such as another hardware device; or it does not
                      support sharing data with OpenCL due to implementation restrictions).
                    </li></ul></div></li>
            <li class="listitem" style="list-style-type: disc">
              <p>
                  <span class="errorname">CL_INVALID_GL_SHAREGROUP_REFERENCE_KHR</span> if a share group
                  was specified for a CGL-based OpenGL implementation by setting the attribute
                  <code class="constant">CL_CGL_SHAREGROUP_KHR</code>, and the specified share group
                  does not identify a valid CGL share group object.
                </p>
            </li>
            <li class="listitem" style="list-style-type: disc">
              <p>
                    <span class="errorname">CL_INVALID_OPERATION</span> if a context was specified as
                    described above and any of the following conditions hold:
                </p>
              <div class="itemizedlist">
                <ul class="itemizedlist" style="list-style-type: disc; ">
                  <li class="listitem" style="list-style-type: disc"> A context or share group object was specified
                      for one of CGL, EGL, GLX, or WGL and the OpenGL implementation does not
                      support that window-system binding API.
                    </li>
                  <li class="listitem" style="list-style-type: disc">
                      More than one of the attributes <code class="constant">CL_CGL_SHAREGROUP_KHR</code>,
                      <code class="constant">CL_EGL_DISPLAY_KHR</code>,
                      <code class="constant">CL_GLX_DISPLAY_KHR</code>, and
                      <code class="constant">CL_WGL_HDC_KHR</code> is set to a non-default value.
                    </li>
                  <li class="listitem" style="list-style-type: disc">
                        Both of the attributes <code class="constant">CL_CGL_SHAREGROUP_KHR</code> and
                        <code class="constant">CL_GL_CONTEXT_KHR</code> are set to non-default values.
                    </li>
                  <li class="listitem" style="list-style-type: disc">
                      Any of the devices specified in the <code class="varname">devices</code> argument
                      cannot support OpenCL objects which share the data store of an OpenGL object.
                    </li>
                </ul>
              </div>
            </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_VALUE</span> if an attribute name
              other than those specified in the table of supported <code class="varname">properties</code>
              for <a class="citerefentry" href="clCreateContext.html"><span class="citerefentry"><span class="refentrytitle">clCreateContext</span></span></a>
              is specified in <code class="varname">properties</code>.
            </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_VALUE</span>
              if <code class="varname">param_name</code> is not
              <code class="constant">CL_CURRENT_DEVICE_FOR_GL_CONTEXT_KHR</code> or
              <code class="constant">CL_DEVICES_FOR_GL_CONTEXT_KHR</code>; or if the size in bytes specified
              by <code class="varname">param_value_size</code> is less than the size of the return type
              shown above for <code class="constant">CL_CURRENT_DEVICE_FOR_GL_CONTEXT_KHR</code>
              or <code class="constant">CL_DEVICES_FOR_GL_CONTEXT_KHR</code>; and
              <code class="varname">param_value</code> is not a NULL value.
            </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_OUT_OF_RESOURCES</span> if there is a failure to allocate
              resources required by the OpenCL implementation on the device
            </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_OUT_OF_HOST_MEMORY</span> if there
              is a failure to allocate resources required by the OpenCL implementation on the host.
            </li>
          </ul>
        </div>
      </div>
      <div class="refsect1">
        <a id="specification"></a>
        <h2>Specification</h2>
        <p>
            <img src="pdficon_small1.gif" />

            <a href="http://www.khronos.org/registry/cl/specs/opencl-1.2-extensions.pdf#page=43" target="OpenCL Spec">OpenCL Specification</a>
        </p>
      </div>
      <div class="refsect1">
        <a id="seealso"></a>
        <h2>Also see</h2>
        <p>
            <a class="citerefentry" href="clCreateContext.html"><span class="citerefentry"><span class="refentrytitle">clCreateContext</span></span></a>
            <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
        </p>
      </div>
      <div xmlns="" class="refsect3" lang="en" xml:lang="en"><a xmlns="http://www.w3.org/1999/xhtml" id="Copyright"></a><h4 xmlns="http://www.w3.org/1999/xhtml"></h4><img xmlns="http://www.w3.org/1999/xhtml" src="KhronosLogo.jpg" /><p xmlns="http://www.w3.org/1999/xhtml"></p>Copyright © 2007-2011 The Khronos Group Inc.
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and/or associated documentation files (the
"Materials"), to deal in the Materials without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Materials, and to
permit persons to whom the Materials are furnished to do so, subject to
the condition that this copyright notice and permission notice shall be included
in all copies or substantial portions of the Materials.
</div>
    </div>
  </body>
</html>
